The age gap "pedophilia" moral panic, spawned by feminism and kicked into overdrive during the #MeToo era that began circa 2017, is a potentially civilization-ruining phenomenon. I am, of course, not referring to very real problems, like grooming gangs in Britain, but the fact that 18-year-old boys are frequently accused of being an "Epstein diddy blud" merely for talking to 17-year-old girls. If you wanted to vaporize our already plummeting birth rates, stigmatizing any age gap larger than that between identical twins is a great way to do it.
Girls typically reach physical sexual maturity (adult secondary sexual characteristics) between the ages of 15 and 17, while boys mature a couple of years later. Yet, it is disturbingly common to conflate an 18-year-old dating a 16-year-old — a relationship between two biological adults, legal everywhere in the West aside from a handful of deranged US states — with a 40-year-old raping a 9-year-old. Apparently, the people who do this have no problem with trivializing actual pedophilia (the sexual abuse of prepubescents), which causes immense and long-lasting harm.
The crux of this issue is that healthy male heterosexuality — the preference for younger but sexually mature women — has effectively been criminalized. Meanwhile, older-female age gap relationships are constantly celebrated by the Gynocratic World Order (see e.g. the safe-horny "dommy mommy" phenomenon), to the extent that female teachers who sleep with their male students are routinely spared jail time and socially excused: "Where was she when I was a student?!"
For all of human history until very recently, older-male-age-gap relationships were regarded as normal and good; the average age gap in America from 1850 to 1950 was 4.5 years. Even today, in face of widespread moral hysteria, the average 23-year-old white man and woman in the West prefer partners who are 2 and 3 years older than themselves, respectively. The evolutionary theory is simple: Men prefer fertile women, women prefer men who can provide for offspring; women are most fertile when young, men accumulate resources with age.
Older-male age-gap relationships produce more children, with total lifetime fertility peaking at +7 years (although the variation from +3 to +13 years is very small). The negative fertility effect of older wives begins immediately at +1 year and declines linearly; at +3.5 years, couples produce 0.5 fewer children, on average. Obviously, this is due to women's limited fertility window, which is much smaller than commonly believed: by age 31, ~10% of women are sterile and ~50% are subfertile (they have difficulty conceiving, decreased egg quality, etc).
In case it were not immediately obvious, I will state explicitly that I do not endorse procreation between e.g. 16-year-old girls and 60-year-old grandpas with mutationally-loaded sperm. The risk of deleterious de novo mutations increases with age, and while the effects are small, they compound over generations, as the botched are no longer filtered out of the genepool via natural selection. Moreover, Joseph Bronski has provided evidence of a paternal age effect on leftism, whereby older fathers produce more hereditarily left-wing babies.
To increase birth rates and reduce dysgenics, early marriage should be encouraged, particularly among the intelligent. Ideally, both husband and wife should be in their late teens to very early 20s. Older-male relationships between young adults (~16-25) should also be destigmatized. Society should be restructured to ensure that intelligent couples can have as many children as possible before age 30-35; reduce time spent in education, prioritize youth for high-paying jobs, give intelligent young men huge lump sums per child (funded by e.g. abolishing welfare), and so on.